This invention relates to a releasable locking coupling or support device for use particularly, but not exclusively, in latching a load, e.g. in a raised position, so that tension in a hauling line can be relaxed, or releasably coupling together two parts or releasably securing one part in or to another part or structure, or forming a rotary coupling between two parts, or providing a releasable load support.
A sail is generally held in its raised position by maintaining tension in the halyard associated with the sail. However the compression force normally exerted on the mast by the tension in the halyard and the weight of the sail can be substantially reduced if, in its raised position, the sail can be latched at its upper end with respect to the mast so that the tension in the halyard can be relaxed. In British Patent Specification No. 2096957 (81.12106) there is described with reference to FIGS. 6 to 8 of the drawings thereof one possible system for suspending a sail in its raised position from a mast head allowing the tension in the associated halyard to be relaxed.